inertia
second law
third law
friction and gravity
Balanced vs. Unbalanced Forces
100

The tendency of an object to resist changes in its state of motion.

What is inertia?

100

The relationship between force, mass, and acceleration is summarized in this equation.

What is F = ma?

100

Forces always occur in pairs that are equal in magnitude and opposite in direction.


What are action-reaction pairs?

100

A force that opposes motion between two surfaces that are in contact

What is friction?

100

Forces that are equal in size and opposite in direction are described by this term

What are balanced forces?


200

This characteristic of an object is the direct measure of its inertia.

What is mass?

200

To accelerate a 1 kg object at a rate of 1 m/s², you need exactly this much force

What is 1 Newton (N)?

200

The force of a rocket pushing hot gases downward is the action. The reaction is this.

What is the hot gases pushing the rocket upward?


200

The force of attraction between any two objects with mass.


What is gravity?

200

 When forces acting on an object are balanced, the net force is this value.

What is zero?

300

A spaceship drifting through space at a constant velocity will continue moving forever in that direction unless acted upon by an external force. This demonstrates which law?

What is Newton's First Law of Motion?

300

If you double the net force applied to an object, you do this to its acceleration

What is double its acceleration?

300

When a swimmer pushes the water backward, the water simultaneously does this to the swimmer.

What is pushes the swimmer forward?

300

The type of friction that prevents an object from starting to move.

What is static friction?

300

An object experiencing balanced forces will do one of two things: remain at rest, or move at this.


What is a constant velocity (constant speed and direction)?

400

 When you make a sharp turn in a car, your body seems to be pushed outward. In reality, your body is trying to do this.

What is continue moving in a straight line?

400

 A 10 N force is applied to a 2 kg object. What is the object's acceleration?

What is 5 m/s²?

400

 A person leans against a wall with a force of 50 N. The wall pushes back on the person with this force.

 What is 50 N?

400

A feather and a hammer are dropped on the Moon (which has no air resistance). They land at the same time because gravity causes the same amount of this.

What is acceleration?


400

These types of forces always cause an object to accelerate (speed up, slow down, or change direction).

What are unbalanced forces?

500

A bowling ball and a tennis ball are both at rest. Which one has more inertia, and why?

What is the bowling ball because it has more mass?

500

You push a shopping cart with a force of 40 N, giving it an acceleration of 2 m/s². What is the mass of the shopping cart?

What is 20 kg?

500

When you jump off the ground, the Earth exerts an upward force on you, but you also exert a downward force on the Earth. Why doesn't the Earth appear to move?

What is because the Earth has so much mass that its acceleration is negligible?

500

This type of friction acts on objects moving through the air or water.


What is fluid friction (or air resistance/drag)?


500

 A skydiver reaching "terminal velocity" is experiencing balanced forces. The upward force of air resistance is equal to this downward force.

 What is gravity (or the skydiver's weight)?